1. Field of the Invention
This invention relates to a photothermographic silver halide material and process for producing images by means of an aminosulfonylhydrazone reducing agent and an ammonia or amine responsive imaging material.
2. Description of the State of the Art
Photothermographic materials for producing silver images are known. Photothermographic materials after imagewise exposure are heated to moderately elevated temperatures without the need for processing solutions or baths to provide a developed image. It has been desirable to produce an image in such materials that requires reduced concentrations of silver halide. This can be done by producing a silver image that is enhanced by a dye image.
Photothermographic materials that produce a silver image and a dye image are known. Such materials are described in, for example, Research Disclosure, Vol. 185, September, 1979, Item No. 18560 and Research Disclosure, Vol. 194, June, 1980, Item No. 19415. These materials can comprise hydrazone silver halide developing agents. These hydrazone developing agents have produced dye images in photothermographic materials by coupling reactions, but have not participated in dye formation by releasing a moiety that activates dye formation. The present invention avoids the need for a means separate from the hydrazone developing agent to release ammonia or an amine that activates dye formation.
The term "photothermographic material" herein means a photothermographic element and photothermographic composition.